Amid race for coronavirus cure, companies promise safe and efficient vaccines

There are more than 150 vaccine candidates around the world right now and many of them will never make it out of the laboratory but the leading candidates are defying medical norms and promising a safe and efficient vaccine by the end of this year.

Here's a round-up of the leading vaccine candidates and how they are faring in clinical trials.

The leading the COVID-19 vaccine race is AstraZeneca - a British-Swedish multinational but last week the company hit a major roablock. Its trials were halted after a British trial volunteer developed serious side-effects. The company called it a "routine" pause after a sweeping review, the UK trials have resumed but authorities in the US and India are yet to give the go-ahead.

Pfizer and Biontech are expanding their stage 3 clinical trials that is if the US food and drug administration(FDA) approves. The companies are on track to meet their initial target of 30,000 volunteers by next week. Late-stage trial results are expected by October but it could take months before the vaccine is declared safe.

US-based Moderna therapeutics is all set to begin it's phase 3 trials. The company is in talks with multiple countries to meet its target of 30,000 volunteers, expect a full scale roll-out by the end of 2020. The target is to produce 1 billion doses per year from 2021.

Russia's Sputnik V is the only vaccine in civil circulation. Two hundred and fifty Moscow residents got it last week and 75 per cent of them are yet to display symptoms with small consignments of Sputnik V being shipped across the country but safety concerns remain as a group of eminent scientists recently raised doubts about the accuracy of Russia's clinical trials.